This is complete rubbish. An egg is alive. So is sperm. So is the zygote. There's no "life begins". It's all life, all the time. That's how life works.

That sperm and egg have both gone through meiosis and are 1n instead of 2n, and when fused create a new 2n thing (still alive) that has, under appropriate conditions, the potential to develop into an adult human is fascinating (and of critical importance to the perpetuation of our species, and many others besides) but of no mystical significance unless your religious beliefs impel you to imbue it so.

(1n and 2n refer to the number of sets of chromosomes, where n is the number of distinct chromosomes, and stated as n to be true across diploid organisms. n=23 in humans.)

The whole concept is carryover from vitalist superstitions because we weren't well-enough informed to recognize that the process could handle "aliveness" without supernatural help. Since we couldn't build alive things with our hands, it seemed like you needed a magical spark to get it going. But it turns out it's all just chemistry: alive (1n) + alive (1n) = alive (2n).

Good grief! 95% of scientists! Not if they understand the question.